Someone who blindly follows the so called metagame, or short: meta of an online multiplayer game. Metafags are the whiny types who complain that you take or use a currently unpopular weapon / strategy or character. The annoying thing about this attitude is, that the meta is being developed by high level professional players, and is thus not as significant for casual players who play the game recreationally and just want to have fun and play the game like they please.
While playing overwatch:
Player1: I will playSoldier.
Player2: No! You musst pick McCree Soldier is not in the current meta!
Player1: Dude, don't be a metafag!
Setting a facebook status that describes a generic class of vaguebooking. Intended to highlight the absurdity and annoyance of vaguebooking. Metavaguebooking has yet to be proven effective at limiting the prevalence of vaguebooking within any particular social sphere. A limitation of its effectiveness is the general cluelessness of vaguebookers.
Facebook status updates:
Lila M: obscure song lyric that only a few will get leaving others to wonder why I'm so moody. emoticon.
David S: Nice metavaguebooking!